The secondary packaging of articles into packages appropriately sized for use by consumers has become an important phase of the manufacturing of many products. Shipment of these consumer packages, however, has created problems in shipping to retailers. Specifically, the small consumer packages have necessitated another step of packaging associated with shipment comprising assembling the consumer packages into layers to be stacked.
One specific example of the primary and seconding packaging of articles and assembly of pallet layers for shipment is found in the distribution of beverages, which are primarily packaged in cans or bottles, then secondarily packaged into consumer multi-packs of various sizes, most frequently six, twelve or twenty-four packs of cans or bottles. The multi-packs are arranged into layers and stacked onto a pallet for shipment from the manufacturer/bottler to the distributer or retailer. The secondary packaging of multi-packs in paperboard, cardboard, film or some combination of cardboard and film is followed by assembly of a number of multi-packs into a layer to be stacked onto a pallet. The assembled layer is then stacked onto the pallet by a palletizer.
Prior art devices and methods for assembling packages into layers for stacking onto a pallet include means for arranging the packages into layers in which the packages are uniformly oriented. However, a disadvantage of such uniform orientation is that, as each layer is stacked on top of the preceding layer, what is essentially created is a number of vertical stacks of the packages. That is, because each layer is identically arranged, vertical columns are the result of each package of a layer being placed squarely on the similarly positioned package of the preceding layer.
As the flexibility of packaging machines has increased, and the number of consumer packages of different sizes has increased, one trend has been the development of smaller consumer packages. The stacking and palletization of the smaller consumer packages has become problematic, however, because the vertical columns of packages created by the stacking of uniform layers have become more unstable. To stabilize the vertical columns of the palletized stacks, prior art stacking techniques and devices have included the use of intermediate layers of cardboard or packing material between layers and, in many instances, the use of film around the palletized stacks.
Typically the packages being assembled into layers and stacked on a pallet are not square, but rather are rectangular and have one side longer than the other. This difference is important and can be advantageous in improving the stability of the palletized stacks. By alternating the orientation of the packages, and assembling individual layers of the palletized stacks differently, the placement of packages onto packages of the preceding layer can be offset so that unstable vertical columns of packages are not created. Rather, the offset of the packages on successive layers allows interlocking to stabilize the palletized stack, thereby reducing or eliminating the need for additional support or stabilizing material such as intermediate layers of cardboard, paperboard, or use of film.
One prior art attempt to solve the problem of the instability of vertical columns by altering the layout of layers of the palletized stack is embodied in U.S. Pat. No. 5,320,478 to Gonsowski, et. al. The apparatus disclosed therein recognized the problem of instability of stacking small items on a pallet and solved the problem by alternately turning packages to vary the layout of successive layers of the stack. In the '478 Gonsowski apparatus a fixed turning mechanism is provided which turns and reorients packages that have been directed toward the turning mechanism by a laning mechanism.
The prior art solutions, including the '478 Gonsowski patent, have failed to provide a flexible means for assembling the packages into layers of various layouts in forming the palletized stack. An apparatus and method by which each layer of a palletized stack may be defined differently is advantageous because it increases the interlocking between layers and thereby, improves the stability of the palletized stack. An apparatus having a programmable package handler which receives each package individually and places and orients the package appropriately to provide a desired layout comprises such a solution and is advantageous over the prior art.
There is thus identified a need for a flexible apparatus and method allowing the assembly of packages into desirable and variable layouts for successive layers of a palletized stack. Alternating the layout of successive layers in this way is beneficial because the stability of the palletized stack is improved.